Symptoms of sluggish cognitive tempo (SCT) have been recognized for nearly 30 years as comprising a semi-independent set(s) of symptoms from the inattentive (IN) and hyperactive-impulsive (HI) symptoms involved in attention-deficit/hyperactivity disorder (ADHD). It has only been within the past decade that research focusing specifically on SCT symptoms and on samples of SCT cases chosen independently from ADHD samples has increased so as to address the question of whether SCT is a distinct condition from ADHD or other disorders. All but two of these studies have focused on children but the two extant large scale studies on adults have replicated those findings. This Commentary highlights not only those findings concerning SCT that appear to be relatively robust, but also those patterns that appear to be emerging yet in need of further research to corroborate their association with SCT, as well as those barely or unexplored areas that may deserve more research. Evidence to date, including the many findings in this special issue, is nearing a critical mass that likely supports the conclusion that SCT is a distinct disorder of attention from ADHD, yet one that may overlap with it in about half of all cases. SCT has unique symptom dimensions and comorbidities from ADHD, probably distinct though lesser domains of impairment and demographic correlates, and perhaps unique cognitive deficits, causes and life course risks. These latter areas, however, are in need of substantially more research as is SCT in adults and treatments specifically designed for cases of SCT. Meanwhile, the name of the condition is premature, implying a known cognitive deficit that is as yet unknown, and is proving derogatory and offensive to patients, leading this author to recommend a change to Concentration Deficit Disorder.